| Listed in parts books | Not catalogued by year yet |
PISTON,BSA M20 +.020
A +.020 oversize piston for the BSA M20.
This is a piston for the BSA M20, machined to +.020 oversize. The M20 is a BSA model, not a Triumph, so if you're working on a Triumph twin this one isn't for your engine.
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The part number and catalog listing both point to the same identity: a BSA M20 piston at the +.020 rebore size. We don't have more detail on this one beyond that, so give us a call and we'll confirm the specifics before you order.
If your cylinder has already been bored to a different oversize, or you're not sure which size you need, check your bore measurement first — oversize pistons are cut to a specific dimension and won't work as a generic substitute.
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